Lid for medical implant

ABSTRACT

A lid for a medical implant that has first and second parts and a mechanism for engaging the implant. The second part is rotatable relative to the first part such that, in use, rotation of the second part relative to the first part causes the engaging mechanism to engage with and attach the lid to the implant.

This application is a 371 filing of International Patent ApplicationPCT/EP2017/064695 filed Jun. 15, 2017, which claims the benefit ofBritish application no. 1610527.2 filed Jun. 16, 2016.

BACKGROUND

The present invention relates to a lid or closure device. In particular,it relates to a lid or closure device for a medical implant, moreparticularly for an ostomy implant.

Ileostomy and colostomy are common operations which may be necessitated,for example, by malignancy or chronic bowel inflammation. The surgery iscalled an ileostomy if the colon and rectum are removed and a colostomyif the rectum alone is removed. Similarly an abdominal urostomy iscreated when the urinary bladder has to be removed due to, for example,bladder cancer. In these operations, a stoma is formed in the abdominalwall to which a bowel segment is connected.

Ostomy is a generic term for any such procedure where a stoma iscreated.

The stoma, in most cases, has to be connected to a bag for thecollection of bodily waste. However, instead of a conventionalileostomy, it is possible to make a reservoir known as a “Kock pouch”from the distal part of the ileum. The pouch is formed in such a waythat a nipple valve is created which serves to close the reservoir,whilst allowing it to be drained intermittently by means of a catheter.This is an example of a so-called continent ileostomy (CI) and it wasformerly an attractive alternative to conventional ileostomy but is nowrarely used. The complexity of the procedure and the high potential forcomplications—most of them related to dysfunction of the continencenipple valve—has deterred many surgeons from adopting the operationtoday.

The ileopouch anal anastomosis (IPAA) is today the gold standardworldwide for these patients but, as with a CI, this operation is alsorisky and failures are common, mostly leading to pouch excision withloss of bowel. Conversion of a failed IPAA to a CI would be a preferableoption but, again, surgeons are reluctant to perform this complex andunreliable technique. Likewise, conversion of a malfunctional orthotopicneobladder or Bricker urostomy would be desirable.

It is known to provide an implant to facilitate connection of a stoma toa lid or bag, for example.

For example, and as illustrated in FIGS. 1 and 2, the applicant'searlier application WO 2014/140344 A1 discloses a percutaneous ostomyimplant 1 comprising a tubular interior section 2, formed mainly ofmesh, and a circular, radially-extending anchoring flange or dermalanchor 3.

The implant 1 is designed to be implanted through the abdominal wall ofa patient and to receive a bowel section drawn through it. Serosaltissue from the bowel section can then grow into the implant 1, throughthe mesh, and attach or grow into surrounding dermal tissue. This canprovide a secure, stable, leak-proof and well-vascularisedtissue-implant junction.

The tubular interior section 2 is attached to an exterior section 4,which, when the implant 1 is implanted in a patient, protrudes from thepatient's body. A groove 6 around the exterior circumference of theexterior section 4 allows a lid, bag or other device (not shown) to beattached to the implant 1.

Once an implant has been implanted into a patient, it is necessary toclose it in some way, or to sealingly connect it to some form ofevacuation means (e.g. a bag or catheter), to prevent leakage of wastefrom the stoma, and to allow waste to be collected and/or disposed ofcleanly. This means that usually some form of lid needs to be attachedto the external end of the implant.

The applicant's earlier application WO 2006/046210 A1 discloses adetachable lid for an implant with mounting means (e.g. a groove orridge) arranged such that the detachable lid can be mounted onto andremoved from an external end of the implant by sliding the lid in adirection perpendicular to the longitudinal axis of the implant.

However, a problem with this method of mounting a lid on an implant isthat it may cause forces to be exerted on the implant which can damagethe tissue-implant junction. It can also be difficult for a patient tomount a lid in this way.

A further problem is that with this sliding method of attachment, it maybe difficult for the lid to seal properly, i.e. in a leak-tight way,with the implant.

WO 2006/046210 A1 also discloses a connecter for connecting an ostomybag to the implant. The connector is arranged to slide the lid off ofthe implant and to connect the bag to the implant.

In the applicant's more recent application WO 2011/039517 A1, a medicalclosure device is disclosed comprising a coupling part and a closurepart (e.g. a lid or cap). The coupling part can be attached to a medicaldevice such as an implant and the closure part can then be attached tothe coupling part to close the implant. The coupling part is acircumferential flexible member delimiting a coupling opening, and isconfigurable between a relaxed configuration where the coupling openingcannot pass over the medical device and a stressed configuration wherethe coupling opening of the coupling part can pass over the medicaldevice. Thus, if the coupling part is squeezed, it will deform from itsrelaxed configuration into a stressed configuration in which it can bepassed over the end of the implant. When pressure is released (i.e. thesqueezing is stopped), the coupling part will attempt to return to therelaxed configuration, thus gripping the end of the implant. The reverseprocedure can be performed to remove the coupling part.

However, a problem with this attachment mechanism is that it may bepossible for the coupling part to become detached from the implant,unintentionally or accidentally, for example if, e.g. by leaning on anobject, pressure is applied to the coupling part causing it to besqueezed into its stressed configuration whereby it may become detachedfrom the implant.

The closure device of WO 2011/039517 A1 is also relatively wide and,when attached to an implant, extends down close to the patient's skinsuch that there is a risk of abrasion and irritation.

Attaching the closure part to the coupling part requires two hands,which may be problematic for a user. Also, as the closure devicecomprises two separate parts (the coupling part and the closure part)there is greater chance of one part becoming lost or dropped, comparedwith a closure device made of a single part. Handling may also be moreinconvenient.

Furthermore, there is a possibility with this closure device that itcould become attached to the implant (locked) in an incorrect position,such that it is not properly seated and sealed on the implant. Forexample, often a user cannot see the lid-implant interface (e.g. due toclothing or stomach being in the way) and so they may attach or lock theclosure device onto the implant in an incorrect position.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provideda lid for a medical implant, the lid comprising a first part, a secondpart and engaging means, wherein the second part is rotatable relativeto the first part (or the first part is rotatable relative to the secondpart) such that, in use, rotation of the second part relative to thefirst part (or vice versa) causes the engaging means to engage with andattach the lid to the implant.

Thus, according to the invention, the second part of the lid can berotated with respect to the first part (or vice versa) to cause the lidto be engaged with and attached to the implant. Accordingly, one part ofthe lid (e.g. the first part) may be kept stationary with respect to theimplant while the lid is being attached thereto. This can reduce oreliminate any forces applied to the implant during attachment, therebyhelping to reduce or eliminate potential damage to an implant-tissuejunction. In addition, a lid with such an attachment mechanism providesa relatively straightforward and easy way for a user to attach the lidto an implant and accidental removal of the lid may be minimised orprevented.

Since the lid may be attached to, or detached from, an implant simply bythe rotation of one of its parts, it may be possible to attach the lidsingle-handedly. This has the benefit of course that a second hand maybe used to hold other items which may be needed, for example, after alid has been removed (e.g. for evacuation/cleaning). (Alternatively, ofcourse, two hands may be used).

Further, since the lid may be attached to, or detached from, an implantsimply by the rotation of one of its parts, users with, e.g., arthritis,weak hands or small hands may be able to perform this procedure.

The medical implant with which the lid may be used could, for example,be an ostomy implant and the present invention is indeed particularlysuited for this purpose. However, the lid is not limited to use withostomy implants, or indeed with any other kind of medical implant, andcould be used for any medical implant or indeed to cover any otherstructure in or over which it is useful to provide a lid with such anattachment mechanism, for example. Examples of medical implants withwhich this lid could be used may include, but are not limited to,colostomy implants, urostomy implants and gastrostomy implants, forexample. A further example of a medical system with an implant, withwhich this lid could be used, is an enteral feeding system (e.g.delivery of nutrition directly into the stomach through a permanenttranscutaneous catheter).

When attached to an implant, the lid, particularly the engaging means,is preferably strong enough and secure enough such that it can withstandoverpressures inside the patient (e.g. due to a build-up of gas).

The simple mechanism described above means that the lid may be, andpreferably is, relatively thin. For example, the lid may have a depth of2.0 cm or less, 2.8 cm or less, 2.6 cm or less, 2.4 cm or less, 2.2 cmor less, 2.0 cm or less, 1.8 cm or less, 1.6 cm or less, 1.4 cm or less,1.2 cm or less, 1.0 cm or less. Providing such a thin lid means that, inuse, the lid is less likely to catch on other objects that a user maycome into contact with such as tables, clothing, door frames, belts,etc.

The lid may have a smooth, rounded top or outer surface, curving down toa point at which it would contact a user's skin. In this way, the lidwould have no corners or projecting parts which could catch againstother objects.

The first part, the second part and the engaging means are preferablyarranged such that, in use, rotation of the second part relative to thefirst part (or vice versa) causes the first part to press against theengaging means. This arrangement can provide a simple mechanism by whichrotation of the second (or first) part causes engaging of the engagingmeans with an implant.

The engaging means could be or comprise any form of engagement mechanismor engager.

The engagement means is preferably located in the second part. Theengaging means could be a part of the second part or, alternatively, theengaging means could be a separate component which, for example, isprovided within the second part.

The engaging means could be or comprise any kind of engagement part e.g.that is suitable for engaging with an implant. For example, the engagingmeans could comprise one or more protruding engagement means orprotrusions (e.g. a projection, ridge, bump, pin, hook) which may bearranged and/or dimensioned so as to fit in a corresponding receivingpart (e.g. a groove, slot, hole or recess) provided on the implant.

Alternatively, or additionally, the engaging means could comprise one ormore recesses or cavities (e.g. groove, slot, hole), provided, forexample, inside the second part, which recesses or cavities may bearranged and/or dimensioned so as to receive or fit over a protrudingengagement means or protrusion (e.g. a projection, ridge, bump, pin orhook) provided on the implant.

Preferably, the engaging means comprises one or more components whichare separate from (not integrally formed with) the second part andis/are preferably contained within the second part but movable, e.g. atleast to some extent, with respect to the second part.

Alternatively or additionally, the engaging means may comprise one ormore fixed or integral engaging components (e.g. fixed to or integrallyformed with the second part) such as a protrusion (e.g. a projection,ridge, bump, pin or hook) or receiving part (e.g. a groove, slot, holeor recess).

The engaging means is preferably arranged such that when the second partis rotated with respect to the first part (or vice versa), the engagingmeans is made to protrude into an engagement recess or cavity providedon the implant.

Alternatively, the engaging means could be arranged such that when thesecond part is rotated with respect to the first part (or vice versa),the engaging means is made to protrude over, around or through anengagement protrusion provided on the implant

In a preferred embodiment, the engaging means comprises one or more,preferably three, pins. Where more than one pin is provided, the two ormore pins may be arranged at, preferably equal, spacings around thesecond part such that the two or more pins can engage with an implantaround its circumference.

Preferably the one or more pins are arranged such that it is alongitudinal side of the one or more pins that would engage with theimplant. However, in an alternative embodiment, the one or more pinscould be arranged such that it is an end of each of the one or more pinsthat would engage with the implant.

The pin or pins is/are preferably supported by the second part, andpreferably movable, at least to some extent, with respect to secondpart.

The pin or pins is/are preferably straight, e.g. with a circularcross-section and preferably rounded ends.

Preferably, the first part, second part and engaging means are arrangedsuch that as the second part is rotated with respect to the first part(or vice versa), the first part also moves further into or onto thesecond part.

Preferably, the first part, second part and engaging means are furtherarranged such that as the first part moves further into or onto thesecond part, the first part exerts a force on, pushes or presses theengaging means, such that the engaging means can engage with an implant.

Thus, by rotating the second (or first) part, the engaging means can bemade to engage with an implant.

In addition, preferably, the first part, second part and engaging meansare arranged such that as the first part moves further into or onto thesecond part, and the first part exerts a force on, pushes or presses theengaging means, the engaging means engages with the implant by beingmoved radially inwards towards the implant and/or (then) upwards,preferably both. By causing the engaging means to move both radiallyinwards and then upwards into (e.g. a groove in) the implant, a moresecure engagement with the implant can be provided.

In addition, as the engaging means are forced upwards into the implant,the first part, and preferably also a seal provided on the lid, e.g. onthe first part, may be drawn down onto the implant, thereby compressingthe seal. This may create a strong and safe seal between the implant andthe lid, which can ideally withstand pressures from intestinal fluid,for example.

In a preferred embodiment, the first part is a cap. For example, thefirst part, or cap, may be substantially circular.

The cap may be formed of a circular top part and a ring-shaped sidepart.

The cap, and preferably its top part, may comprise one or more grooves.

For example, the cap may comprise a first groove which preferably runsfrom one side of the top part, preferably across the centre of the toppart, to the opposite side of the top part. A recess may be providedalong one or both sides of the groove.

The cap may comprise a second groove provided, for example, in the baseof the first groove. The base of the first groove may be otherwise flat.The second groove is preferably narrower than the first groove andpreferably runs from one side of the top part, e.g. where the firstgroove starts, preferably across the centre of the top part, andpreferably almost, but not quite, to the opposite side of the top part.The centrelines of the first and second grooves are preferablyco-linear.

On the base of the second groove, and preferably spaced along itscentreline, there may be provided one or more, preferably twoupwardly-projecting bumps. The one or more bumps preferably do notproject any higher than the depth of the second groove, such that theydo not project up into the first groove.

The side part of the cap preferably projects downwards from thecircumferential edge of the top part.

Within the cap and preferably on an outer surface of the side part,there may be provided one or more, preferably three, preferablyidentical and preferably equally circumferentially spaced apart, groovesor recesses. Each groove or recess may comprise an upwardly-extendingpart or a circumferentially-extending part, and preferably both anupwardly-extending part and a circumferentially-extending part. Theupwardly-extending part may extend upwards from the bottom of the sidepart towards, but not as far as, the top part. The groove may thencontinue in a circumferentially-extending part from the top of theupwardly-extending part circumferentially around the side part.Preferably, each groove does not extend as far around the side part asthe next groove so that a gap without any groove is present between thegrooves.

The upwardly-extending part of each groove may be shallower than thecircumferentially-extending part. Thus, there may be a small step “down”(or radially inwards with respect to the cap) from theupwardly-extending part to the circumferentially-extending part, whichmay start just above it.

In addition, or alternatively, there is preferably a (relatively small)ridge or bump provided along or at a top end of the upwardly-extendingpart before the circumferentially-extending part.

In the circumferentially-extending part of each groove there may be a(relatively thin) ridge, preferably along most but not the entire lengthof the centreline of the circumferentially-extending part. The ridgepreferably does not extend as far as either end of thecircumferentially-extending part.

Preferably, as each circumferentially-extending part extends around theside part, it also extends slightly upwardly, such that eachcircumferentially-extending part preferably slopes upwards around theside part.

Preferably, on the underside of the top part, and e.g. inside the sidepart, there is a radially inner groove and/or a radially outer groove.The radially outer groove may be bounded or formed by the radially innersurface of the side part and a first circular wall. The radial innergroove may be bounded or formed by the first circular wall and a secondcircular wall.

Preferably, the second part is a base, the base being preferablysubstantially ring-shaped, e.g. with a substantially circular opening inits centre.

For example, the base may comprise a side part and, for example, aradially inwardly extending part which may extend radially inwardly froma lower (in use) circumferential edge of the side part. The radiallyinwardly extending part may form or comprise, e.g. at its centre, thesubstantially circular opening of the base.

On the outer surface of the side part or base there are preferablygripping regions with, e.g., ridges to facilitate gripping of the base,e.g. for rotation and/or when placing it over an implant.

Preferably, the base has a rounded or curved bottom, e.g. where the sidepart joins the radially inwardly extending part. Alternatively oradditionally, the lid (e.g. its base) and/or the implant is/aredimensioned such that when the lid is attached to an implant there is asmall gap between the patient's skin and the bottom of the lid/base.This means that there would be little or no abrasion on a patient'sskin, e.g. when sitting or bending.

The base is preferably dimensioned so that the first part or cap can fitinside it, preferably exactly. In other words, an inner diameter of thebase is preferably equal to an outer diameter of the first part or cap.

On the upper or inner surface of the base or, preferably, its radiallyinwardly extending part, there is preferably a, e.g. circumferential,groove which may be formed by the inner surface of the side part and acircular ridge, for example, e.g. extending upwardly from, e.g., theinner circumference of the inwardly extending part. The ridge ispreferably dimensioned so as to fit in a (e.g. radially outer) groove ofthe first part or cap when the lid is assembled.

At one or more, preferably three, preferably equally, circumferentiallyspaced apart positions along the circumferential groove there are, forexample, one or more recesses or straight grooves, which may be slightlydeeper than the circumferential groove. The one or more recesses orstraight grooves are preferably arranged and dimensioned such that theycan hold, support or contain the engagement means.

Above, e.g. the centre point of, each of these recesses or straightgrooves, and extending from, e.g., the inner surface of the side part,there may be one or more, preferably three, preferably circular guideprojections. The one or more guide projections are preferablydimensioned so as to fit in, and slide along, a groove provided in thecap or first part.

Associate with each recess or straight groove, for example at either endof each straight groove, preferably on a radially inner side, there maybe provided a resilient tongue which can, for example, act as a weakspring (e.g. against the engagement means in each recess or straightgroove).

A recess is preferably provided in the side part above one of the guideprojections. The recess is preferably dimensioned such that a slider(described below) may fit or be slid through it.

The lid preferably comprises means for providing tactile feedback to auser indicating when the lid is in an engaged and/or disengaged state.For example, the ends of the recess in the side part may such tactilefeedback when a part of a slider, or other rotation means (see below),for example, abuts against them (e.g. following rotation of theslider/base).

Preferably, the first part is or can be snap fitted into the secondpart. This is an easy and secure way to assemble the two parts whilststill ensuring that they can rotate with respect to each other.

Preferably, the first and second parts comprise complementary guidemeans, or guiding parts, for example to facilitate their relativerotation.

One part (e.g. first or second part) may comprise a projection and theother part a groove for guiding the projection.

For example, the complementary guide means may comprise one or moregrooves provided on the first part or the second part, and one or morecomplementary protruding parts or projections provided on the other ofthe first part and the second part, whereby the one or more protrudingparts are arranged to extend into the one or more grooves, therebyallowing the first and second parts to rotate relative to each other.

Preferably, the first and second parts are arranged such that as thesecond part is rotated relative to the first part (or vice versa), thefirst part is also made to move (e.g. by complementary guide means)axially with respect to the second part. As such, as the first part isrotated with respect to the second part, the first part may be made tomove towards or away from, or into or out of, the second part, dependingon the direction of rotation.

The first part may comprise or have connected thereto a rotation means(or anvil) for facilitating rotation of the second part relative to thefirst part (or vice versa). For example, the rotation means may protrudefrom, or be able to protrude from, the first part to facilitate rotationof the second part, e.g. by holding the first part stationary.Alternatively, the rotation means could be used to facilitate rotationof the first part, whilst the second part is held stationary.

Although the term “rotation means” is used, it will be appreciated thatthe rotation means itself need not necessarily rotate, it may merelyfacilitate rotation of another part. Thus, in this application,“rotation means” should be interpreted as a means for facilitatingrotation of the second or first part (or “rotation facilitation means”),which need not itself necessarily be rotated. Indeed, in a preferredform of use, the rotation means is held stationary and used as a kind of“anvil” or holding means. For example, the rotation means may be, andpreferably is, used to hold the first part stationary whilst the secondpart is rotated with respect to the first part. However, alternatively,the rotation means could be used to rotate the first part with respectto the (stationary) second part.

The rotation means is preferably retractable between a first position inwhich the second part may be rotated relative to the first part (or viceversa) (the lid is “unlocked”), and a second position in which thesecond part may not be rotated relative to the first part (or viceversa) (the lid is “locked”). Thus, when the rotation means is in thesecond (locked) position, inadvertent rotation of the first part may beprevented.

The rotation means may, for example, be a slider arranged to slide,preferably radially, in a groove, for example, provided in the firstpart.

The rotation means is preferably dimensioned so as to extend across adiameter of the first part.

In a preferred embodiment, the rotation means is substantiallyrectangular but may have curved ends, e.g. to match or correspond to thecircumference of the first part.

The rotation means preferably has a curved upper surface with, forexample, the curvature of this surface extending along the length of therotation means.

On a bottom surface of the rotation means and, for example, towards oneend, there may be provided one or more, preferably two, preferablyparallel ridges, e.g. of equal length and preferably extending along a(relatively short) length of the rotation means.

Additionally or alternatively, a bump is preferably provided on thebottom surface of the rotation means. For example, the bump may beprovided in a region between two ridges and the bump may extend betweenthe two ridges. The bump is preferably curved. The ridges preferablyextend slightly further along the length of the rotation means than thebump.

The lid preferably comprises means for providing tactile and/or audiblefeedback (preferably both) (e.g. tactile and/or audible feedbackpart(s)) to a user for indicating when the lid is in locked/unlockedstates/positions. For example, interaction between one or more bumps,ridges or grooves provided on the rotation means and/or first part (e.g.in a groove in the first part) may provide such feedback. Preferably,the bump and/or one or more ridges provided under the rotation means,and/or the one or more upwardly-projecting bumps and/or an end of thesecond groove on the first part, are arranged such that interactionbetween them many provide such feedback.

A preferably curved groove is provided on the bottom surface of therotation means, e.g. around its longitudinal mid-point. The curvedgroove preferably extends from one edge of the rotation means towards,but preferably not as far as, the opposite edge. The curved groovepreferably has a radius of curvature on its inner edge corresponding tothat of the outer circumference of the first part, or the innercircumference of the top of the second part.

On preferably the upper surface of the rotation means, e.g. at one end,there may be provided a marking or sign such as a single or double-endedarrow, showing, for example, the direction(s) in which the rotationmeans is to be moved or slid, in use.

The rotation means may comprise, e.g. at an (other) end of e.g. itsupper surface, a gripping area, with one or more ridges or othergripping means, e.g. for facilitating the moving or sliding of therotation means, in use.

Along one or preferably both edges of the rotation means, e.g. from itsbottom side, there may be provided one or more projecting parts. Oneprojecting part may be broken, or have a gap, at one point, e.g. whereit extends over a curved groove provided on the bottom surface of therotation means. The projecting part(s) is/are preferably dimensioned soas to fit in recesses present inside a groove provided in the firstpart.

As described above, the rotation means may, in addition to providing ameans for rotating the second (or first) part, provide a means forlocking/unlocking the lid (a locking means). However, it is alsopossible for a locking means to be provided separately from, and inaddition to, the rotation means, e.g. as a separate part.

Thus, in some embodiments, the lid may comprise locking means forlocking/unlocking the lid. Preferably, the locking means is movablebetween a first position in which the first part may be rotated relativeto the second part (the lid is “unlocked”), and a second position inwhich the first part may not be rotated relative to the second part (thelid is “locked”). Thus, when the locking means is in the second (locked)position, inadvertent rotation of the first part may be prevented.

The locking means could be any kind of locking part capable ofallowing/preventing rotation of the second part relative to the firstpart (or vice versa). For example, the locking means could comprise aretractable member (e.g. a pin or slider) which can be moved between afirst, e.g. inserted, position, in which rotation of the second partrelative to the first part (or vice versa) is prevented (the lid islocked), and a second, e.g. retracted, position, in which rotation ofthe second part relative to the first part (or vice versa) is possible(the lid is unlocked). For example, in its first position, theretractable member could extend, e.g. in an axial direction, through thefirst part into a hole or recess in the second part, thereby preventingtheir relative rotation and locking the lid.

Preferably, the locking means is arranged such that, when the lid ispositioned on an implant, the locking means can only be moved from itsunlocked to its locked position when the lid is properly engaged withthe implant. Thus, when the lid is not properly engaged, the lid isprevented from being locked. This can help to prevent improperpositioning of the lid on an implant, which could result in leakage.

The lid preferably further comprises a seal, e.g. for providing sealingengagement with the implant. The seal may be provided in or be part ofthe first part.

For example, the seal may be a sealing ring, e.g. provided in apreferably circular groove in the first part.

Alternatively, the seal, e.g. a sealing ring, may be injection mouldedinto the first part. This could be done by first moulding the firstpart, e.g. in a moulding tool, and then removing an insert from the toolsuch that sealing material (i.e. material for forming the seal) can thenbe moulded directly onto the first part (or the first part could bemoved to a second chamber in the moulding tool, shaped such that thesealing material will form a seal when moulded into place on the firstpart).

The sealing ring is preferably circular and dimensioned so as to fit ina radially inner groove in the first part. The sealing ring preferablyhas a flat side and a curved side, and is preferably positioned in thefirst part with its flat side facing towards the bottom of the radiallyinner groove (i.e. upwards, in use). One or more, preferably two, smallprojections may be provided, e.g. opposite each other, on the sealingring, and may extend e.g. perpendicularly from the flat side of thering.

Other forms of seal could also be used.

Preferably, as the second part is rotated with respect to the first part(or vice versa), the seal can be made to move towards and to pressagainst a surface of the implant, e.g. by relative axial movement of thefirst part.

Thus, the lid preferably comprises a dual locking mechanism, e.g. as thesecond part is rotated with respect to the first part (or vice versa)the engaging means engage with the implant and the seal is compressedagainst the implant. Once engaged and sealed in this way, the lid canpreferably be locked (e.g. by placing the rotation means in a lockedposition) in a position in which the engaging means cannot disengagefrom the implant and/or the seal cannot become decompressed. The lid,e.g. the first part, preferably comprises one or more visual signs orindicators to show at what position the lid is in anopen/closed/locked/unlocked position, for example.

The lid may be made of plastic metal, wood, a combination material, acomposite material and/or rubber. Preferably, the lid is preferably madeof plastic, e.g. polypropylene or silicone.

Preferably, the first and second parts of the lid are made of differentmaterials, e.g. different kinds of plastic. This is because some (e.g.plastic) materials can tend to stick to each other when under somepressure. Thus, to minimise the possibility of this kind of frictionoccurring between the first and second parts, it is preferred that theyare made from different materials.

The engaging means may be made or metal, e.g. stainless steel, fibre,hardwood, a soft metal, or plastic, for example.

However, preferably the engaging means is made of a softer material thanthat of the (e.g. titanium) implant. This can help to ensure that theengaging means wears out before the edge of a groove in the implant, forexample, (or other receiving part for the engaging means) over which theengaging means moves.

For example, the engaging means could be made of a plastic/polymeric andpossibly fibre-reinforced material.

Preferably, the engaging means, and all parts of the lid, are made ofnon-magnetic materials (e.g. aluminium, brass) for MRI compatibility.

The seal is preferably made of a medical grade soft polymer.

The lid may be cleaned with normal household methods, e.g. including oneor more of rinsing, detergent, soap, boiling, bleaching and alcohol.

The present invention also relates to an implant with a lid as describedabove or below attached thereto.

The present invention also relates to a method of manufacturing a lidfor a medical implant, e.g. as described above, the method comprising:providing a first part, a second part and engaging means; and assemblingthe first part, the second part and the engaging means to form a lidsuch that the first part is rotatable relative to the second part and,in use, rotation of the first part relative to the second part causesthe engaging means to engage with and attach the lid to the implant. Thefirst part, second part and/or engaging means are preferably asdescribed above.

The method of manufacturing a lid may comprise one or more of thefollowing steps:

providing, inserting or locating the engaging means in the second part;

providing, inserting or locating a seal, e.g. as described above, in thefirst part;

providing, inserting or locating a rotation means, e.g. as describedabove in the first part.

These steps may be performed in any order and/or in parallel with one ormore of each other.

The method may alternatively or additionally comprise (e.g. preferablyafter the above steps) inserting or locating the first part (with sealand/or rotation means, if provided) in the second part (e.g. withengaging means).

The first part may then be rotated with respect to the second part.

The rotation means may, for example, be inserted or slid into e.g. agroove in the first part.

In a preferred method, the second part is placed with a radiallyinwardly extending part located at the bottom. Engaging means, e.g. oneor more, preferably three, pins, is/are then preferably placed in thesecond part, e.g. in each of (three) preferably straight grooves.

The first part is preferably placed with a groove, e.g. a radially innergroove, facing upwards. The seal is then preferably placed into thegroove, e.g. with a flat side facing downwards into the groove.

The first part is preferably placed e.g. with an upper surface facingupwards. The rotation means may be inserted into or connected to thefirst part, e.g. by sliding or inserting the rotation means into agroove or recess in the first part.

As the rotation means is slid into the first part, resistance may befelt as a e.g. curved bump provided under the rotation means (e.g. asdescribed above) meets one or more bumps on the first part (e.g. asdescribed above). Some additional force may therefore be required tocause the e.g. curved bump to pass over the one or more bumps on thefirst part.

After the rotation means has been inserted into the first part, the bumpon the ends of one or more ridges on the rotation means (e.g. asdescribed above) may abut against a closed end of a groove in the firstpart (e.g. as described above) and the rotation means may be preventedfrom being inserted any further into or across the first part.

The one or more ridges and the closed end of the groove are preferablypositioned such that at this point, i.e. when the one or more ridgesabut against the closed end of groove, a curved groove (e.g. asdescribed above) on the underside of the rotation means is positionedsuch that it extends around the outer circumference of the first part.

The rotation means should preferably be moved or slid into thisposition, i.e. as described above, before further steps of assembly ofthe lid described below are performed.

The assembled first part (e.g. with a rotation means and/or seal asdescribed above) is preferably inserted into or placed around theassembled second part (e.g. with the engaging means, as describedabove).

In order to do this, the assembled first part is preferably positionedwith its upper surface facing upwards, and the assembled second part ispreferably positioned, for example on a level surface, with a radiallyinwardly extending part (e.g. as described above) located at the bottomor facing downwards. The first part is further preferably positionedsuch that one or more walls or boundaries of one or more grooves in thefirst part, e.g. one or more upwardly-extending parts of grooves in thefirst part, are each located directly above a guide, e.g. a preferablycircular guide projection, e.g. as described above, provided in thesecond part.

The assembled first part is further preferably positioned such that itsengaging means (if provided) slightly overlaps a recess in a side partof the second part (e.g. as described above).

The assembled first part and the assembled second part are, e.g. afterthe above alignment procedure, preferably pressed or snapped together,e.g. by pressing the first part into or over the second part, such that,for example guides provided in the second part pass over, for example,ridges provided e.g. at a top end of each upwardly-extending part, and,preferably, then into circumferentially-extending parts.

As the assembled first part has preferably been positioned such that theengaging means slightly overlaps a recess in a side part of the secondpart, part of a top edge of the second part may be fitted into thecurved groove on the underside of the engaging means, if provided.

Next, the assembled first part is preferably rotated, e.g. clockwisewhen viewed from above, with respect to the second part, (or viceversa), by, for example, pushing or pulling or otherwise moving therotation means. By moving the rotation means in this way, the first partis preferably rotated as far as it can be, e.g. until the guides in thesecond part reach upper ends (e.g. of circumferentially-extending parts)of grooves in the first part (e.g. opposite to the ends where thecircumferentially-extending parts meet the upwardly-extending parts) andmay thus be prevented from moving further.

As the first part is rotated in this way, it is also preferably drawn(further) down into or onto the second part, e.g. due to a slope ofgrooves in the first part.

When the first part has been rotated as far as it can be, e.g. when theguides in the second part reach ends of grooves in the first part, therotation means is preferably located inside the recess in the side ofthe second part.

Next, the rotation means is preferably pushed inwards, e.g. through therecess and/or a groove in the first part, until, for example, therotation means is prevented from moving further, e.g. by abuttingagainst a side part of the second part. At this point, the rotationmeans is preferably positioned across the (e.g. entire) diameter of thelid, within, for example, a groove on the first part.

The rotation means is, at this point, preferably flush with thesurrounding area of the first part.

In addition or alternatively, the longitudinal length of the rotationmeans is preferably equal to an outer diameter of the second part suchthat, at this point, the rotation means does not project outwardly frombase.

This means that the lid provides a relatively smooth and continuousouter surface, which would not, for example, get caught on clothing orother objects which could apply a force against it and potentiallydamage the tissue-implant junction. It also means that the lid isdiscrete for a user.

Once the lid has been assembled, e.g. in the above way, it may beprovided e.g. to a patient or other user, for fitting onto e.g. animplant.

The present invention also relates to a method of attaching a lid for amedical implant, e.g. as described above, to an implant, the lidcomprising a first part, a second part and engaging means, wherein themethod comprises: placing the lid over a protruding end of the implantand then rotating the second part relative to the first part (or viceversa), such that the engaging means engages with and attaches the lidto the implant. The first part, the second part and/or the engagingmeans are preferably as described above.

The method preferably first comprises extending (e.g. sliding) arotation means (e.g. as described above) from the first part, such thatthe rotation means may be used to rotate the first part. For example,starting from a lid with rotation means inserted in or across the firstpart, before the lid is fitted on an implant, the rotation means may beextended or slid outwardly, e.g. along a groove in first part.

The first part may be rotated, e.g. anti-clockwise with respect to thesecond part when viewed from above, such that the first part preferablyrises up out of the second part slightly. At this point, the rotationmeans may, for example, be only slightly overlapping (or not overlappingat all) a recess in the second part (e.g. as described above).

The lid may then be ready to be fitted onto an implant.

A user preferably holds a projecting end of the rotation means and mayplace the lid over an exterior section of the implant.

The second part is then preferably rotated, e.g. bypushing/pulling/moving the rotation means, for example in ananti-clockwise direction with respect to the first part when view fromabove (or vice versa) until, for example, the rotation means ispositioned completely in a recess in the second part (e.g. as describedabove).

As the second part is rotated with respect to the first part (or viceversa), the first part is preferably drawn down into or onto the secondpart, for example by virtue of one or more guides in the second part(e.g. as described above) being made to slide along grooves, forexample, in the first part (e.g. as described above).

As the first part is drawn down into or onto the second part in thisway, a side part of the first part preferably moves down, e.g. into agroove inside the second part, and forces the engaging means to engagewith the implant.

The second part preferably comprises one or more resilient tonguesarranged for pressing against the engaging means.

Preferably, the engaging means may be forced, e.g. by a part of thefirst part as it moves down into or onto the second part, radiallyinwardly, preferably against the one or more resilient tongues, andpreferably slightly upwardly into a groove or other recess in theimplant, e.g. a groove around an exterior circumference of an exteriorsection of the implant.

This engaging of the engaging means with the implant can secure and holdthe lid onto the implant and, for example, prevent users, clothing orother objects, from being able to simply move or pull the lid straightoff of the implant, e.g. unintentionally.

In addition, as the first part is drawn down into or onto the secondpart, a seal (e.g. as described above), provided for example on anunderside of the first part, may be compressed against the implant, e.g.against an upper surface of an exterior section of the implant, therebyforming a leak-proof seal between the implant and the lid.

Once the lid has been attached to the implant, the rotation means ispreferably slid or moved back to its unextended position, e.g. backacross the lid, e.g. through and into a groove on the first part. Thus,once the lid has been attached to an implant, the rotation means may beretracted such that it is no longer protrudes from the lid.

The present invention also relates to a method of removing a lid for amedical implant, e.g. as described above, from an implant, the lidcomprising a first part, a second part, and engaging means, wherein themethod comprises: rotating the second part relative to the first part(or vice versa) such that the engaging means disengages from theimplant, and then removing the lid from the implant. The first part, thesecond part and/or the engaging means are preferably as described above.

In order to remove a lid from an implant, the reverse procedure to thatdescribed above may be performed.

For example, the lid may start with a rotation means in a retracted ornon-extended position with respect to the rest of the lid. The rotationmeans may then be extended, e.g. pulled outwards for example through agroove in the first part. When extended, for example, the rotation meansmay be used to rotate the second part, e.g. in a clockwise direction,with respect to the second part (or vice versa). This rotationpreferably causes the first part to move upwards and slightly out/off ofthe second part, such that, for example, a part (e.g. a side part) ofthe first part no longer forces or holds the engaging means inengagement with the implant. The one or more resilient tongues, forexample, preferably cause the engaging means to be retracted from theimplant, e.g. from a groove in the implant. At this point, as the firstpart has moved upwards slightly, a seal is preferably no longercompressed against the implant.

The user may then lift the lid off of the implant, e.g. with little orno resistance.

After removal of a lid from an implant, it should preferably be washed.

The concept of a lid with a locking means is viewed as inventive in itsown right and thus, viewed from a further aspect, there is provided alid for a medical implant, the lid comprising engaging means and lockingmeans, wherein the locking means are movable between a locked position,in which the engaging means may not engage with/disengage from animplant, and an unlocked position, in which the engaging means mayengage with/disengage from an implant.

Thus, when the locking means is in the locked position (i.e. the lid islocked), the lid may not be, e.g. accidently, disengaged from an implantand accidental removal of the lid from an implant may be prevented.Conversely, when the locking means is in the unlocked position (i.e. thelid is unlocked), the lid may be engaged with/disengaged from theimplant. Thus, the lid may be locked onto an implant in its engagedstate, and a conscious and active step must be taken such that the lidmay be unlocked and then disengaged from the implant.

The locking means could be or comprise a locking part suitable forlocking/unlocking the lid, and preferably also engaging/disengaging theengaging means.

The phrase “locking the lid” means putting the lid into a locked statewherein its engaging means cannot be engaged with/disengaged from animplant. Conversely, the phrase “unlocking the lid” means putting thelid into an unlocked state wherein its engaging means can be engagedwith/disengaged from an implant.

The locking means could, for example, be the rotation means as describedabove.

Alternatively, the locking means could be any kind of locking partcapable of allowing/preventing rotation of the second part relative tothe first part (or vice versa). For example, the locking means couldcomprise a retractable member (e.g. a pin or slider) which can be movedbetween a first, e.g. inserted, position, in which rotation of thesecond part relative to the first part (or vice versa) is prevented, anda second, e.g. retracted, position, in which rotation of the second partrelative to the first part (or vice versa) is possible. For example, inits first position, the retractable member could extend, e.g. in anaxial direction, through the first part into a hole or recess in thesecond part, thereby preventing their relative rotation.

The lid may comprise any or all of the other features described above orbelow.

Viewed from a further aspect, there is provided a method of locking alid for a medical implant, the lid comprising engaging means and lockingmeans, the method comprising moving the locking means into a lockedposition in which the engaging means may not engage with/disengage froman implant. The lid may be as described above or below, and the methodmay comprise any of the further features described above or below.

Viewed from a further aspect, there is provided a method of unlocking alid for a medical implant, the lid comprising engaging means and lockingmeans, the method comprising moving the locking means into an unlockedposition in which the engaging means may engage with/disengage from animplant. The lid may be as described above or below, and the method maycomprise any of the further features described above or below.

The concept of a lid with compression means that can be used to draw thelid down onto an implant is also viewed as inventive in its own rightand thus, viewed from a further aspect, there is provided a lid for amedical implant, the lid comprising a seal and compression means,wherein the compression means is arranged such that, when the lid isplaced over an implant, activation or use of the compression meanscauses at least the seal to move down towards the implant such that theseal is compressed against the implant.

As such, the compression means can be used to cause the seal to movedown onto the implant, such that the seal is compressed into preferablysealing engagement with the implant, thereby provided a leak-proof seal.

The seal (e.g. as described above) is preferably provided on anunderside of the lid.

The lid preferably also comprises engaging means, e.g. as describedabove. The compression means is preferably arranged such that activationof the compression means causes the engaging means to engage with theimplant (as well as the lid and its seal to move down towards theimplant such that the seal is compressed against the implant), forexample as described above. Thus, the compression means can preferablybe used to control both the attachment or engagement of the lid to animplant, as well as the sealing of the lid to an implant.

The compression means could be or comprise any kind of compression part,e.g. that is suitable for compressing the seal against the implant.

For example, and e.g. as described above, the compression means could beor comprise a rotation means which can be used to cause the lid (or apart of the lid) to rotate downwards onto the implant, thereby causingthe seal to be compressed onto the implant. The compression means could,for example, be the rotation means as described above.

Alternatively or additionally, the compression means could comprise apushbutton on, for example the top of, the lid, or one or more,preferably two, protruding parts/levers/buttons on, e.g. the side of,the lid to push/squeeze.

The engaging means could comprise one or more fixed parts and one ormore movable parts.

For example, as a fixed part, the engaging means could comprise a fixededge, ridge or other protrusion provided on the lid for engaging with acorresponding groove or indentation on the implant (or vice versa). Theedge, ridge or other protrusion could, for example, be provided on oraround a lower inner rim of the lid, e.g. its base. It could, forexample, cover half or less than half (e.g. around a third or less,around a quarter or less) of an inner circumference of the lid.

As one or more movable parts the engaging means could comprise one ormore levers, pins, hooks or other movable engaging means. The one ormore movable parts could be distributed, preferably evenly, along theremaining circumference of the lid, i.e., that not covered by the fixedpart(s).

In one embodiment, the lid could comprise a edge or ridge covering thein circumference along one quadrant of the lid and one or more,preferably two or three, levers, pins or hooks, distributed, preferablyevenly, over the circumference of the remaining three quadrants.

With such a lid, the lid could be slid onto an implant, for example, toengage the fixed part(s) with the implant, and then the movable part(s)could be activated (e.g. by the compression means) to further engagewith the implant, and, preferably, compressing a seal provided on thelid with the implant to ensure sealing engagement of the lid with theimplant.

The lid may comprise any or all of the other features described above orbelow.

A method of sealing a lid for a medical implant with or to an implant,the lid comprising a seal and compression means, the method comprisingplacing the lid over the implant and activating or using the compressionmeans to cause the seal to move down towards the implant such that theseal is compressed against the implant. The lid may be as describedabove or below, and the method may comprise any of the further featuresdescribed above or below.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will now be shown by wayof example only and with reference to the accompanying drawings, inwhich:

FIG. 1 shows a perspective view of an ostomy implant;

FIG. 2 shows a side view of the ostomy implant of FIG. 1;

FIG. 3 shows an exploded perspective view of components of a lidaccording to an embodiment of the invention;

FIGS. 4(a)-(c) show a top, side and perspective view, respectively, ofthe lid shown in FIG. 3;

FIGS. 5(a)-(h) show a perspective, bottom, side, cross-sectional, top,side, cross-sectional and a further cross-sectional view, respectively,of the cap of the lid shown in FIG. 3;

FIGS. 6(a)-(d) show a bottom, top, side and end view, respectively, ofthe slider of the lid shown in FIG. 3;

FIGS. 7(a)-(i) show a perspective, bottom, cross-sectional, side,further side, detail, further detail, further cross-sectional andfurther cross-sectional view, respectively, of the base of the lid shownin FIG. 3;

FIGS. 8(a) and (b) show side and end views, respectively, of a pin ofthe lid shown in FIG. 3;

FIGS. 9(a)-(c) show a top, cross-sectional and side views, respectively,of the sealing ring of the lid shown in FIG. 3;

FIGS. 10(a)-(c) show steps for inserting the pins of FIG. 8 into thebase of FIG. 7;

FIGS. 11(a)-(e) show steps for inserting the sealing ring of FIG. 9 intothe cap of FIG. 5;

FIGS. 12(a)-(c) show steps for inserting the slider of FIG. 6 into thecap of FIG. 5;

FIG. 13 shows how to insert the assembled cap of FIG. 12 into theassembled base of FIG. 10;

FIG. 14 shows a perspective view of a lid following the step of FIG. 13;

FIGS. 15(a)-(d) shows steps for finalising the assembly process of thelid following the step of FIG. 13;

FIG. 16 is a flow diagram showing the steps for assembly of the lid;

FIGS. 17(a)-(d) show steps for fitting a lid of FIG. 3 onto an implant;

FIGS. 18(a)-(e) show steps for removing a lid of FIG. 3 from an implant;and

FIG. 19 shows a perspective view of an implant fitted with a lid of FIG.3.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 3 shows an exploded perspective view of the components of a lid 10according to an embodiment of the invention.

The components of the lid 10 consist of: a substantially ring-shapedbase 11, a substantially circular cap 12, a slider 13, a sealing ring 14and three pins 15. The respective components 11, 12, 13, 14, 15, of thelid 10 are described in more detail below.

FIGS. 4(a)-(c) show top, side and perspective views, respectively, ofthe lid 10 of FIG. 3.

FIGS. 5(a)-(h) show a perspective, bottom, side, cross-sectional, top,side, cross-sectional and a further cross-sectional view, respectively,of the cap 12 of the lid 10 shown in FIG. 3.

The cap 12 is circular and is formed of a circular top part 28 and aring-shaped side part 29.

In the top part 28 there is a first groove 20 which runs from one sideof the top part 28, across the centre of the top part 28, to theopposite side of the top part 28. The upper surface 28 a of the top part28 slightly projects over the two sides of the first groove 20 forming asmall recess 22 along either side of the groove 20.

Within the first groove 20, in its base (which is otherwise flat), thereis a second groove 21. The second groove 21 is narrower than the firstgroove 20 and runs from the one side of the top part 28 where the firstgroove 20 starts, across the centre of the top part 28, and almost, butnot quite, to the opposite side of the top part 28. The centrelines ofthe first and second grooves 20 and 21 are co-linear.

On the otherwise flat base of the second groove 21, and spaced along itscentreline, there are two upwardly-projecting bumps 23 a and 23 b. Thebumps 23 a and 23 b do not project any higher than the depth of thesecond groove 21, so they do not project up into the first groove 20.These bumps 23 a and 23 b are provided and positioned so as to give adefinite “click” sound and feel feedback to the user, when the slider ispushed all the way into each of its two end positions. The “click” soundand feel feedback is provided as the bumps 23 a and 23 b pass over acorresponding bump 31 provided on the bottom surface of the slider 13(see below).

On the upper surface 28 a of the top part 28 there are two logos 27 aand 27 b marking locked and unlocked positions of the lid 10.

The side part 29 projects downwards from the circumferential edge of thetop part 28.

Within the outer surface of the side part 29 are provided threeidentical and equally circumferentially spaced apart grooves 24. Eachgroove 24 consists of an upwardly-extending part 24 a and acircumferentially-extending part 24 b. The upwardly-extending part 24 aextends upwards from the bottom of the side part 29 towards, but not asfar as, the top part 28. The groove 24 then continues in thecircumferentially-extending part 24 b from the top of theupwardly-extending part 24 a circumferentially around the side part 29.Each groove 24 does not extend as far around the side part 29 as thenext groove 24 so that a gap without any groove is present between thegrooves 24.

The upwardly-extending part 24 a of each groove 24 is shallower than thecircumferentially-extending part 24 b of each groove 24. Thus, there isa small step “down” (or radially inwards with respect to the cap 12)from the upwardly-extending part 24 a to the circumferentially-extendingpart 24 b, which starts just above it. In addition, there is a smallridge 24 d provided along the top end of the upwardly-extending part 24a before the drop “down” into the circumferentially-extending part 24 b.

In the circumferentially-extending part 24 b of each groove 24 there isa thin ridge 24 c along most but not the entire length of the centrelineof the circumferentially-extending part 24 b. The ridge 24 c does notextend as far as either end of the circumferentially-extending part 24b.

When the lid 10 is assembled, the three ridges 24 c are in contact withthree corresponding circular guide projections 44 located on the insideof the base part 11 (see below).

As each circumferentially-extending part 24 b extends around the sidepart 29, it also extends slightly upwardly, such that eachcircumferentially-extending part 24 b slopes upwards around the sidepart 29.

On the underside of the top part 28, and inside the side part 29, thereis a radially inner groove 25 and a radially outer groove 26. The radialouter groove 26 is bounded or formed by the radially inner surface ofthe side part 29 and a first circular wall 26 a. The radial inner groove25 is bounded or formed by the first circular wall 26 a and a secondcircular wall 25 a.

FIGS. 6(a)-(d) show a bottom, top, side and end view, respectively, ofthe slider 13 of the lid 10 shown in FIG. 3.

The slider 13 is dimensioned so as to extend across a diameter of thelid 10, when assembled. As such, the slider 13 is substantiallyrectangular but has slightly curved ends 38 a 38 b to match thecircumference of the lid 10. The slider 13 has a curved upper surface 37with the curvature of this surface 37 extending along the length of theslider 13 (i.e. when assembled, across the diameter of the lid 10).

On the bottom surface of the slider 13 and towards one end 38 b, thereare two parallel ridges 30 a, 30 b of equal length extending along ashort length of the slider 13. Extending between the two ridges 30 a, 30b is a curved bump 31. The ridges 30 a, 30 b extend slightly furtheralong the length of the slider 13 than the bump 31.

Around the mid-point of the slider 13, and on its bottom surface, is acurved groove 32 extending from one edge 39 a of the slider 13 towardsbut not as far as the opposite edge 39 b. The curved groove 32 has aradius of curvature on its inner edge corresponding to that of the outercircumference of the cap 12.

At one end of the upper surface 37 of the slider 13 there is marked adouble-ended arrow 24, showing the directions in which the slider 13 isto be slid, in use. At the other end of the upper surface 37, there is aridged area 33 with ridges for facilitating the sliding of the slider13, in use.

Along each edge 39 a, 39 b of the slider 13, from its bottom side, thereis a projecting part 36 b, 36 a, respectively. The projecting part 36 bis broken, or has a gap 36 b′, at one point where it extends over thecurved groove 32. The projecting parts 36 a, 36 b are dimensioned so asto fit in the recesses 22 present inside the first groove 20 of the cap12.

FIGS. 7(a)-(i) show a perspective, bottom, cross-sectional, side,further side, detail, further detail, further cross-sectional andfurther cross-sectional view, respectively, of the base 11 of the lid 10shown in FIG. 3

The base 11 is ring shaped and has a side part 40 and a radiallyinwardly extending part 42 which extends radially inwardly from a lower(in use) circumferential edge of the side part 40.

On the outer surface of the side part 40 there are gripping regions 41with ridges to facilitate gripping of the base 11, for example in use,e.g. for rotating the base 11.

The base 11 is dimensioned so that the cap 12 can fit inside it exactly.

On the upper or inner surface of the radially inwardly extending part 42there is a circumferential groove 45 formed by the inner surface of theside part 40 and a circular ridge 45 a extending upwardly from the innercircumference of the inwardly extending part 42. The ridge 45 a isdimensioned so as to fit in the radially outer groove 26 of the cap 12,when the lid 10 is assembled.

At three equally circumferentially spaced apart positions along thecircumferential groove 45 there are three straight grooves 43 which areslightly deeper than the circumferential groove 45. Above the centrepoint of each of these straight grooves 43, and extending from the innersurface of the side part 40, there are three circular guide projections44. These circular guide projections 44 are dimensioned so as to fit in,and slide along, the groove 24 of the cap.

These circular guide projections 44 are provided on short flexible armsand, as the base 11 or cap 12 is rotated, the guide projections 44 arearranged to travel over the ridges 24 c provided in the grooves 24, asdescribed above. As the guide projections move over the ridges 24 c,this produces a slight breaking action to (or frictional force exertedagainst) the rotation between the cap 12 and the base 11, this providesa nice and solid “quality” feeling to a user of the lid. At the tworotational end positions, i.e. when the guide projections 44 are ateither end of the grooves 24, the ridges 24 c disappear and the breakingaction does too, thereby creating distinct end positions, with thefrictional force provided by the ridge 24 c meaning that the cap 12 andthe base 11 do not unintentionally rotate against each other.

In the radially inwardly extending part 42 beneath each circular guideprojection 44, there is a rectangular hole 47. These holes 47 are notrelated to the function of the lid 10, but are present due to theinjection moulding process used to make the lid 10. These holes 47 areneeded for movable anvils in the injection moulding tooling to createthe circular guide projections 44 described above.

At either end of each straight groove 43, on a radially inner side,there is a resilient tongue 49 which can act as a weak spring.

A recess 46 is provided in the side part 40 above one of the circularguide projections 44. The recess 46 is dimensioned such that the slider13 can be slid through it.

FIGS. 8(a) and (b) show side and end views, respectively, of the pins 15of the lid 10 shown in FIG. 3. The pins 15 are straight with a circularcross section and curved ends. Three pins 14 are provided for each lid10 and they are dimensioned so as to fit in the three straight grooves43 of the base 11.

FIGS. 9(a)-(c) show a top, cross-sectional and side views, respectively,of the sealing ring 14 of the lid 10 shown in FIG. 3. The sealing ring14 is circular and dimensioned so as to fit in the radially inner groove25 of the cap 12. The ring 14 has a flat side 14 b and a curved side 14c. Two small projections 14 a are provided opposite each other on thesealing ring 14 and extend perpendicularly from the flat side 14 b ofthe ring 14. The small projections 14 a do not serve any purpose oncethe lid 10 is assembled but merely serve to identify the flat side 14 bof the ring 14 more clearly, so that it can be inserted into the innergroove 25 of the cap 12 in the correct orientation.

Before the lid 10 is assembled from its component parts 11, 12, 13, 14,15 and then packaged, it is cleaned and disinfected. The cleaningprocess includes ultrasonic cleaning-disinfection with 70% ethanol for3-5 minutes. After this, and before assembly and packing, all parts 11,12, 13, 14, 15 are dried by heat (maximum 70° C.) or in room air in aprotected area to avoid condensation in the packaging. Cleaning isperformed in a clean and controlled environment, in conjunction withassembly and packaging in sealable bags.

When the lids 10 are produced in volume, the lid parts 11, 12, 13, 14,15 will be moulded in a clean-room environment directly. This means nocleaning (as described above) will be necessary before (or after)assembly.

The assembly process for the lid 10 will now be described.

FIGS. 10(a)-(c) show steps for inserting the three pins 15 into the base11 for assembly of the lid 10.

First, as shown in FIG. 10(a), the base 11 is placed with its radiallyinwardly extending part 42 located at the bottom. A pin 15 is thenplaced in each of the three straight grooves 43, as shown in FIG. 10(b).The final configuration of the base 11 and pins 15 after performingthese steps is shown in FIG. 10(c).

FIGS. 11(a)-(e) show steps for inserting the sealing ring 14 into thecap 12 for assembly of the lid 10.

First, cap 12 (as shown in FIG. 11(a)) is placed with its radially innergroove 25 facing upwards, as shown in FIG. 11(b). The sealing ring 14 isthen placed into the radially inner groove 25 with its flat side 14 bfacing downwards into the groove 25, and its curved side 14 c facingupwards out of the groove 25, as shown in FIGS. 11(c) and (d). The finalconfiguration of the cap 12 and sealing ring 14 after performing thesesteps is shown in FIG. 11(e).

In an alternative embodiment, the cap 12 and sealing ring 14 are formedtogether using a two-step injection moulding process (forming first thecap 12 and then the sealing ring 14 on the cap 12) so that the methodshown in FIGS. 11(a)-(e) is not required.

FIGS. 12(a)-(c) show steps for inserting the slider 13 into the cap 12for assembly of the lid 10.

First, as shown in FIG. 12(a), the cap 12 is placed with its uppersurface 28 a facing upwards and the slider 13 is placed with its uppersurface 37 facing upwards. The end 38 a of the slider 13 is then slidinto the first groove 20 of the cap 12 along axis L. The slider 13 isslid into the first groove 20 at the end of the first groove 20 wherethe second groove 21 extends to right to the circumferential edge of thecap 12. As the slider 13 is slid into the first groove 20, theprojecting parts 36 a, 36 b of the slider 13 slide through the recesses22 along either side of the groove 20.

As the slider 13 is slid through the first groove 20, resistance is feltas the curved bump 31 under the slider 13 meets the bumps 23 b and then23 a in the second groove 21 of the cap 12. Some additional force istherefore required to cause the curved bump 31 to pass over the bumps 23b and then 23 a in the second groove 21.

After the bump 31 on the slider 13 has passed over the bump 23 a in thesecond groove 21, the ends of the parallel ridges 30 a, 30 b abutagainst the closed end 21 a of the second groove 21 and the slider 13cannot be slid any further across the cap 12. The ridges 30 a, 30 b andthe ends 21 a of the second groove 21 are positioned such that at thispoint, i.e. when the parallel ridges 30 a, 30 b abut against the closedend 21 a of the second groove 21, the curved groove 32 on the undersideof the slider 13 extends around the outer circumference of the cap 12,as shown in FIGS. 12(b) and (c). The slider 13 should be slid into thisposition, i.e. where the ends of the parallel ridges 30 a, 30 b abutagainst the closed end 21 a of the second groove 21 and the curvedgroove 32 on the underside of the slider 13 extends around the outercircumference of the cap 12 before the further steps of assembly of thelid 10 described below are performed.

FIG. 13 shows how to insert the assembled cap 12 (i.e. with the slider13 and sealing ring 14 inserted in it) into the assembled base 11 (i.e.with the pins 15 inserted in it).

The assembled cap 12 is positioned with its upper surface 28 a facingupwards and the assembled base 11 is positioned, for example on a levelsurface, with its radially inwardly extending part 42 located at thebottom or facing downwards. The cap 12 is positioned such that theupwardly-extending parts 24 a of the grooves 24 in the cap 12 are eachlocated directly above a circular guide projection 44 in the base 11.The assembled cap 12 (with slider 13) is further positioned such thatthe slider 13 slightly overlaps the recess 46 in the side part 40 of thebase 11.

The assembled cap 12 and the assembled base 11 are then pressed orsnapped together, by pressing the cap 12 into the base 11, such that thecircular guide projections 44 in the base 11 pass over the ridges 24 dat the top end of each upwardly-extending part 24 a, and into thecircumferentially-extending parts 24 b.

As the assembled cap 12 (i.e. including the slider 13) has beenpositioned such that the slider 13 slightly overlaps the recess 46 inthe side part 40 of the base 11, part of the top edge 48 of the base 11is fitted into the curved groove 32 on the underside of the slider 13.

FIG. 14 shows a perspective view of a lid 10 comprising the base 11, cap12 and slider 13 (as well as the pins 15 and sealing ring 14, which arenot visible) following the steps associated with FIG. 13 describedabove.

FIGS. 15(a)-(d) shows the steps for finalising the assembly process ofthe lid 10 following the steps of FIG. 13 described above.

First, the cap 12 and slider 13 are rotated clockwise with respect tothe base 11, when viewed from above, by pushing the slider 13 along pathP, as shown in FIG. 15(a). By pushing the slider 13, the cap 12 isrotated as far as it can be, i.e. until the circular guide projections44 reach the upper ends of the circumferentially-extending parts 24 b ofthe grooves 24 (opposite to the ends where thecircumferentially-extending parts 24 b meet the upwardly-extending parts24 a) and are thus prevented moving further.

As the cap 12 is rotated in this way, it is also drawn further down intothe base 11 due to the slope of the circumferentially-extending parts 24b in the cap 12.

When the cap 12 has been rotated as far as it can be, i.e. when thecircular guide projections 44 reach the upper ends thecircumferentially-extending parts 24 b of the grooves 24, the slider 13is located inside the recess 46 of the base 11, as shown in FIG. 15(b).

Next, as shown in FIG. 15(c), the slider 13 is pushed inwards, alongarrow A through the recess 46 and first groove 20, until it is preventedfrom moving further by abutting against the side part 40 of the base 11.At this point, the slider 13 is positioned across the entire diameter ofthe lid 10, within the first groove 20, as shown in FIG. 15(d). Thelongitudinal length of the slider 13 is equal to the outer diameter ofthe base 11 such that, at this point, the slider 13 does not projectoutwardly from base 11 at all.

FIG. 16 is a flow diagram showing the steps for assembly of the lid 10from its component parts 11, 12, 13, 14, 15.

At step 50, the pins 15 are inserted into the base 11, as shown in FIGS.10(a)-(c) and described above.

At step 51, the sealing ring 14 is inserted into the cap 12, as shown inFIGS. 11(a)-(e) and described above. In an alternative embodiment, inwhich the cap 12 and sealing ring 14 are/have been formed together (e.g.in a two-step injection moulding process, as described above), this step51 is not needed.

At step 52, the slider 13 is inserted into the cap 12, as shown in FIGS.12(a)-(c) and described above.

In FIG. 16, step 51 is performed before step 52 but in other embodimentsstep 52 is performed before step 51, and in yet other embodiments steps51 and 52 are performed in parallel.

In FIG. 16, step 50 is performed in parallel with steps 51 and 52 but inother embodiments steps 50, 51 and 52 are performed in series in anyorder, e.g. 50 then 51 then 52; or 51 then 52 then 50. The othersequences of these steps would also be possible.

After steps 50-52 have been performed (in whichever order, and in seriesor in parallel), step 53 is performed in which the cap 12 (with theslider 13 and sealing ring 14) is inserted into the base 11 (with pins15), as shown in FIGS. 13 and 14 and described above.

Next, at step 54, the cap 12 is rotated with respect to the base 11, asshown in FIGS. 15(a) and (b) and described above.

Finally, at step 55, the slider 13 is slide into the groove 20 in thecap 12, as shown in FIGS. 15(c) and (d) and described above, and isready for packaging, use or storage.

Once the lid 10 has been assembled in this way, it can be provided to apatient for fitting onto an implant 1.

FIGS. 17(a)-(d) show steps for fitting the lid 10 onto an implant 1.

Starting from a lid 10 with the slider 13 slid in across the cap 12,before the lid 10 can be fitted on an implant 1, the slider 13 must beslid outwardly along the groove 30 in the cap 12. The cap 12 must thenbe rotated anti-clockwise with respect to the base 11 when viewed fromabove (or vice versa), such that the cap 12 rises up out of the base 11slightly, and the slider 13 is only slightly overlapping the recess 46.The lid 10 is then ready to be fitted onto an implant 1.

As shown in FIG. 17(a) a user holds the projecting end of the slider 13and places the lid 10 over the exterior section 4 of the implant 1.

The slider 13 is then used to hold the cap 12 stationary while the base11 is rotated in an anti-clockwise direction with respect to the cap 12when viewed from above, as shown by the arrow in FIG. 17(b)(alternatively, the slider 13 could be used to rotate the cap 12 in aclockwise direction with respect to the base 11 when view from above,while the base 11 is held stationary) until the slider 13 is positionedcompletely in the recess 46 of the base 11.

As the base 11 is rotated anti-clockwise with respect to the cap 12 (orvice versa), the cap 12 is drawn down into the base 11 by virtue of thecircular guide projections 44 being made to slide along upwardly slopingcircumferentially-extending parts 24 b of the grooves 24 around the cap12.

As the cap 12 is drawn down into the base 11 in this way, the side part29 of the cap 12 moves down into the circumferential groove 45 insidethe base 11, thereby forcing the three pins 15 located in the threestraight grooves 43 around the circumferential groove 45 radiallyinwardly, against the resilient tongues 49 and slightly upwardly intothe groove 6 around the exterior circumference of the exterior section 4of the implant 1. This engaging of the pins 15 against the inner uppersurface of the groove 6 of the implant 1 secures and holds the lid 10onto the implant 1 and prevents users from being able to simply move orpull the lid 10 straight off of the implant 1, intentionally orunintentionally.

In addition, as the cap 12 is drawn down into the base 11, the sealingring 14 on the underside of the cap 12 is compressed against the uppersurface of the exterior section 4 of the implant 1 thereby forming aleak-proof seal between the implant 1 and the lid 10.

Once the lid 10 has been secured and sealed in this way, the slider 13is slid back across the rest of the lid 10, through groove 20, as shownin FIG. 17(c), so that it is no longer protruding radially outwardlyfrom the rest of the lid 10, as shown in FIG. 17(d).

In order to remove a lid 10 from an implant 1, the reverse procedure isperformed, as shown in FIGS. 18(a)-(d).

The lid 10 starts with the slider 13 in a “slid in” position withrespect to the rest of the lid 10, as shown in FIG. 18(a). The slider 13is then pulled outwards through the groove 20 in the cap 12, as shown inFIG. 18(b). When fully drawn out, the slider 13 is then used to hold thecap 12 stationary while the base 11 is rotated in a clockwise directionwith respect to the cap 12 (or, alternatively, the base 11 is heldstationary and the slide 11 is used to rotate the cap 12 in ananti-clockwise direction with respect to the base 11). This rotationcauses the cap 12 to move upwards and slightly out of the base 11 suchthat the side part 29 no longer forces or holds the pins 15 in thegroove 6 around the implant 1 and the resilient tongues 49 cause thepins 15 to be retracted from the groove 6. In addition, the sealing ring14 is no longer compressed down against the upper surface of theexterior section 4 of the implant 1.

The user can then lift the lid 10 off of the implant 1 with little or noresistance.

After removal of the lid 10 in this way from an implant 1, it should bewashed, as shown in FIG. 18(e).

FIG. 19 shows a perspective view of an implant 1′ (not implanted in apatient) fitted with a lid 10.

The lid 10 is reusable but with a limited life. It can be used by apatient for up to two weeks before a new lid 10 must be used.

The lid 10 is dimensioned to fit an implant with an outer diametercorresponding to an inner diameter of the lid 10. However, the lid 10can be fitted onto implants 1, 1′ with differing axial lengths and/ordifferent internal structures.

The slider 13, the cap 12 and the base 11 are all made of plastic byinjection moulding.

The pins 15 are made of stainless steel.

In an alternative embodiment, the pins 15 are made of plastic. This canensure that the pins 15 wear out long before the edge of the groove 6 inthe implant 1, 1′ over which the pins 15 move.

The sealing ring 14 is made of a medical grade soft polymer.

Each lid 10 is provided to a user in a disinfected state in asemi-sealed individual bag (i.e. the bags are perforated along one sideto be easy to tear open. However, the lid 10 does not need to besterile.

The lid 10 (except the pins 15 and sealing ring 14) is skin-coloured andis intended to be inconspicuous.

The lid 10 is designed such that one lid size can fit different implantsizes. For example, implants can be provided with different innerdiameters (i.e. the diameter of the opening through the implant), e.g.optimised for different sizes (thicknesses/diameters) of ileum. However,as the implants (particularly their exterior sections) have the sameouter diameter, the same lid 10 may fit implants with different innerdiameters.

The sealing ring 14 is located sufficiently close to the outer diameterof the lid 10 such that the lid 10 may fit implants even with arelatively large inner diameter (and, consequently, a relatively thinexterior section top surface against which the sealing ring 14 can becompressed).

The lid 10 can also fit implants with different axial lengths, providingthat the outer diameter of the exterior section of the implant is thesame.

The fact that the same lid 10 may fit implants of different sizes isadvantageous because there is no need to make different sized lids forimplants with different inner diameters and/or axial lengths. This makesmanufacturing simpler, saves time and costs, and is safer (there is nochance of putting a wrong sized lid 10 on an implant).

What is claimed is:
 1. A lid for a medical implant, the lid comprising:a first part; a second part having a side; and engaging means located inthe second part or integrally formed with the second part; wherein; thesecond part is configured to be assembled with the first part; in usewhen the second part is assembled with the first part, the second partis rotatable relative to the first part, or the first part is rotatablerelative to the second part; and relative rotation of the first part orthe second part in use causes the first part to engage the engagingmeans and causes the engaging means to be moved, with respect to theside of the second part, such that said engaging means engages with theimplant and thereby attaches the lid to the implant.
 2. The lid asclaimed in claim 1, wherein the first part, the second part and theengaging means are arranged such that, in use when the lid is detachedfrom the implant, rotation of the second part relative to the firstpart, or rotation of the first part relative to the second part, causesthe first part to press against the engaging means such that saidengaging means is moved with respect to the side of the second part andengages with the implant and thereby attaches the lid to the implant. 3.The lid as claimed in claim 1, wherein the engaging means comprises atleast one pin.
 4. The lid as claimed in claim 1, wherein the first partis a cap.
 5. The lid as claimed in claim 1, wherein the second part is abase, the base being ring shaped.
 6. The lid as claimed in claim 1,wherein the first part is snap fitted into the second part.
 7. The lidas claimed in claim 1, wherein the first and second part comprisecomplementary guide means.
 8. The lid as claimed in claim 7, wherein thecomplementary guide means comprise one or more grooves provided on thefirst part or the second part, and one or more complementary protrudingparts provided on the other of the first part and the second part,whereby the one or more protruding parts are arranged to extend into theone or more grooves, thereby allowing the first and second parts torotate relative to each other.
 9. The lid as claimed in claim 1, whereinthe first and second parts are arranged such that as the second part isrotated relative to the first part, or the first part is rotatedrelative to the second part, the first part is also made to move axiallywith respect to the second part.
 10. The lid as claimed in claim 1,wherein the first part comprises or has connected thereto a rotationmeans for rotating the first part relative to the second part, andwherein the rotation means is a movable member or slider arranged toradially move or slide in a groove or recess provided in the first part.11. The lid as claimed in claim 10, wherein the rotation means ismovable between a first position in which the second part may be rotatedrelative to the first part, or the first part may be rotated relative tothe second part, and a second position in which the second part may notbe rotated relative to the first part, or the first part may not berotated relative to the second part.
 12. The lid as claimed in anypreceding claim 1, wherein the lid further comprises a seal.
 13. The lidas claimed in claim 12, wherein the seal is provided in or is part ofthe first part.
 14. The lid as claimed in claim 12, wherein the seal isa sealing ring.
 15. The implant attached to the lid of claim
 1. 16. Amethod of manufacturing the lid as claimed in claim 1, the methodcomprising: providing the first part, the second part and the engagingmeans, the engaging means located in the second part or integrallyformed with the second part; and assembling the first part, the secondpart and the engaging means to form the lid such that the second part isrotatable relative to the first part, or vice versa, and, in use,rotation of the second part relative to the first part, or vice versa,causes the engaging means to be moved, with respect to the side of thesecond part, whereby said engaging means engages with the implant andthereby attaches the lid to the implant.
 17. A method of attaching thelid as claimed in claim 1, the lid comprising the second part assembledwith the first part, to the implant, the method comprising: placing thelid over a protruding end of the implant; and then rotating the secondpart relative to the first part, or vice versa, such that the engagingmeans moves with respect to the side of the second part, whereby saidengaging means engages with the implant and thereby attaches the lid tothe implant.
 18. A method of removing the lid as claimed in claim 1, thelid comprising the second part assembled with the first part, to theimplant, the method comprising: rotating the second part relative to thefirst part, or vice versa, such that the engaging means moves withrespect to the side of the second part, whereby said engaging meansdisengages from the implant; and then removing the lid from the implant.19. The lid as claimed in claim 1, wherein the lid is arranged suchthat, in use, when the lid is placed over a protruding end of theimplant and the engaging means is disengaged, rotation of the first partrelative to the second part in a first direction causes a movement ofthe engaging means with respect to the side of the second part, wherebysaid engaging means engages with the implant and thereby attaches thelid to the implant.
 20. The lid as claimed in claim 19, wherein the lidis arranged such that, in use when the engaging means is engaged withthe implant, rotation of the first part relative to the second part in asecond direction causes a movement of the engaging means with respect tothe side of the second part, whereby said engaging means disengages fromthe implant and thereby detaches the lid from the implant.
 21. The lidas claimed in claim 1, wherein the lid is arranged such that, in use,when the second part is rotated with respect to the first part (or viceversa), the engaging means is made to: protrude into an engagementrecess or cavity provided on the implant; or protrude over, around orthrough an engagement protrusion provided on the implant.
 22. The lid asclaimed in claim 1, wherein the lid is arranged such that, in use whenthe first part is assembled with the second part, rotation of the firstpart relative to the second part causes the engaging means to be movedradially inwards, with respect to the side of the second part, such thatsaid engaging means engages with the implant and thereby attaches thelid to the implant.